海气相互作用的随机-动力理论

在长期天气过程和气候形成的理论中,海洋起着重要的作用。但是海洋是一种缓慢流动的介质,比热也远比大气的比热大,从大范围运动角度来看,大气运动特别大尺度天气过程,相对说来比较活跃和变化速度较快,这种较快的天气起伏,将影响海水的潜热和感热输送,使海温发生变化,然而海温的气候变化是一个缓慢过程,而且是一个大范围现象,因此可以将天气过程的起伏看成一种随机强迫,从这一观点出发,Frankignoul and Hasselman采用简单的随机模型,探讨了海温异常的成因与变化,得到了引人注目。

THE STOCHASTIC-DYNAMIC THEORY OF AIR-SEA INTERACTION

The air-sea interaction is a key problem in long-range forecast and dynamic climatology. This paper presents a simple model of SST variability in which the interaction between SST and atmospheric motion is briefly studied.The model is formulated by second order linear differential equation describing the evolution of the SST is stochastically forced by the white noise represnting day to day weather fluctuations. This result demonstrates that the stochastic forcing of SST is important if strong positive feedback between SST and atmospheric motion exists.The theoretical distribution of spectrum of SST is more improved than that of the first order Markovian model of Froukignoul.These results are in well agreement with the observations.